Paper board



Patented Apr. 28, 1925.

I UNITED STATES PATENT LEO J'. SPAEDER, 0F ERIE, PENNSYLVANIA.

EPAJPER BOARD.

Application filed October 28, 1924. Serial No. 74,353.

checker boards. Such boards have usual- 1y been formed of wood but ithas .been sometimes attempted to. form them from solid paper boardstock. The wood is rather expensive and the solid paper board stock isinclined to warp and lack rigidity.-

Tn carrying out my invention 1 use a fiat corrugated paper stock havinga corrugated core with flat sides and cover this completely with a coverstrip or glazed paper of sufiicient stifi'ness to make rigid,squaret-urned edges for this corrugated stock. Thus a board ofsufficient rigidity to form a checker board without the box flanges cant' be made and there is no tendency to warp and the edges are given'anappearance of solidity and thickness that adds very much its appearance.

The invention is illustrated in the accompanying drawings as followsFig. 1 shows a perspective view of the checker board.

Fig.1. 1 a fragment of a checker board face.

Fig. 2 a section on the line 2-2 in Fig. 1. Fig. 3 a plan view of thecover blank.

Fig. 4 an enlarged sectional view of an edge of the board.

The corrugated'board is made up of the central corrugated core 1 withthe flat sides 2. The boards are cut' to the proper size. This gives theunsightly and readily crushed edges; The cover paper has one face 3.Immediately adjacent to this face are the edges 4; which are of a widthcorresponding to the thickness of the corru gated board.' The coverblank is scored on the lines 5'5 at each margin of the face forming theboard edge. Flaps 6 are formed on three of the sides in continuation ofthe strips 4 and an inside coverface 7 is formed in continuation of theremaining side. This blank is placed on the outer surface of the board,the parts 4 adjacent to the flaps 6 are carried up along the edges ofthe board and the flaps 6 fol ed in and pasted on the face of the board.The part 4: adjacent to the face 7 is carried up along its edge and thepart 7 pasted down on the remaining side of the board. Thus the board isentirely encased with a cover of sufficient stiffness and thickness,usually a glazed stock, and the square-turned rigid corners are formed,closing, bracing and giving rigidity to .the edges of the corrugatedboard so that the board as a whole has the rigidity and sightliness of awood board, the corrugated board preventing the tendency to warp andgiving rigidity, the cover board giving rigidity and. squareness ofcontour at the edges. The two boards are hinged together by a hingestrip 8 which is secured to two ad acent edges and ordinarily extends at9 along the faces.

What I claim as new is 1. A flat paper board formed of corrugated paperwith a corrugated core and flat sides, and a cover of paper foldedaround the corrugated board with square-turned corners forming a flatedge of the thickness of the corrugated board, said cover board being ofa stiffness to give rigidity to the edge. I

2. A flat-paper board formed of corrugated paper with a corrugated coreand flat sides, and a cover of paper folded around the corrugated boardwith square-turned corners forming a fiat edge of the thickness 3. Aflat paper board formed of corrugated paper with a corrugated core andflat sides, and a cover of paper folded around the corrugated board withsquare-turned corners forming a Hat edge of the thickness of thecorrugated board, said cover board being of a stiffness to give rigidityto the edge, said cover having united opposing covering faces of thedimensions of the corrugated board.

4. A checker board formed of flat sections, each section formed of afiat paper edge, the sections being hinged by a strip board having acorrugated core with flat secured to the opposing edges of the flatsides and a. cover of paper folded around board. 10 the corrugated boardwith square-turned In testimony whereof I have hereunto set cornersforming a flat edge of the thickness my hand.

of the corrugated board, said cover board being of a stiffness to giverigidity to the LEO J. SPAEDER.

